201006772 六、發明說明： t 明戶斤屬^奸々貝j 技術領域 本發明係有關一種依據浮法所得之板玻璃的製造裝置 及其製造方法’特別是有關一種將自還原氣體環境之熔融 金屬浴槽拉出之高溫的玻璃帶搬運至氧化氣體環境之徐冷 部，以製造板玻璃的板玻璃之製造裝置及板玻璃之製造方 背景技術 於建築用板玻璃、汽車用板玻璃、及顯示器用板玻璃 等之玻璃板中，依據使用浮浴槽（熔融錫浴槽）之浮法所 得的板玻璃之製造裝置及製造方法以往以來已被知悉（專 利文獻1)。 依據π法所得的板玻璃之製造方法係將溶融玻璃供給 • i浮浴槽的熔賴表面上’且在㈣錫浴上將熔融玻璃成 形成連續的板狀者，並將在炼融錫浴中成為預定寬度之連 續玻璃板的高溫玻璃帶從熔融錫表面拉出，將其徐冷且切 斷成預定大小的玻璃板之製法。 從熔融錫浴表面之玻璃帶的拉出係藉由以被稱為提升 輥⑽。相U)之輥在熔融錫浴的出口舉起玻璃帶並搬運 而進行。以下_提核存在的地㈣為锡槽箱201006772 VI. Description of the invention: t. The invention relates to a device for manufacturing sheet glass obtained by a float method and a method for manufacturing the same, in particular to a molten metal in a self-reducing gas environment. The high-temperature glass ribbon pulled out by the bath is transported to the cold portion of the oxidizing gas environment, and the manufacturing device for the sheet glass of the sheet glass and the manufacturing of the sheet glass are used for the construction board glass, the automobile sheet glass, and the display. In a glass plate such as a plate glass, a manufacturing apparatus and a manufacturing method of a plate glass obtained by a float method using a float bath (melted tin bath) have been conventionally known (Patent Document 1). The method for manufacturing the plate glass obtained by the π method is to supply the molten glass to the molten surface of the i-floating bath and to form the molten glass into a continuous plate on the (four) tin bath, and to be in the smelting tin bath. A high-temperature glass ribbon which is a continuous glass plate of a predetermined width is drawn from the surface of the molten tin, and is cooled and cut into a glass plate of a predetermined size. The pull-out of the glass ribbon from the surface of the molten tin bath is referred to as a lift roller (10). The roll of the phase U) is carried out by lifting the glass ribbon at the outlet of the molten tin bath and carrying it. The following _ mentioning the existence of the ground (four) is the tin tank
槽箱 (dross 業已 -„卩及徐 3 201006772 v爐徐冷該連結部及徐冷爐存在的區域以下稱為徐冷 部。在該徐冷部支撐搬運玻璃帶之棍以下稱為徐冷輥。由 於浮浴槽之溶融錫容易氧化，因此錫浴槽之氣體環境係藉 由鼠（N2)氣與氫（Η。氣之混合氣體在還原氣體環境（％ 濃度1 12/、氧（〇2)濃度：l〇〇ppm以下）保持於正 壓。又，與浮浴槽連通之錫槽箱也保持於正壓之還原氣體 環境。而且，徐冷爐之氧化氣體環境的〇2濃度為5〜21%。 先前技術文獻 專利文獻 專利文獻1:國際公開W0 02/〇51767號公報 Γ瘦^月内溶L】 發明概要 發明欲解決之課題 但是，依據浮法之習知板玻璃之製造裝置是利用分隔 壁而將作為還原氣體環境之成形部與作為氧化氣體環境之 徐冷部分隔者’但是由於使玻璃帶自成形部通過至徐冷 爐，因此玻璃帶的上面與分隔壁之間設有若干間隙。 因此，成形部之錫槽箱内的氫氣會通過前述間隙而漏 至徐冷部，與高溫之玻璃帶附近的氧氣反應而產生氫火 焰’而有本來已慢慢冷卻之玻璃帶因氫火焰而被再加熱的 問題。由於起因於該玻璃帶之再加熱，於製造出之板玻璃 產生彎曲且產生殘餘應力’因此會有板玻璃之品質降低的 問題。特別是，在電漿顯示器面板用、液晶顯示面板用等 之顯示器用板玻璃及電子用途玻璃（太陽電池蓋玻璃、磁 201006772 碟基板等）上被要求要降低料及_應力。而 且’於錫槽箱中’由於玻璃帶之底面係藉由提升輥而橫跨 其寬度方向全區連續地接觸，因此不會發生因氫氣從玻璃 帶之底面與提升輥間漏至徐冷部所產生之氫火焰。 本發明係鑒於如此之情事而完成者，其目的在於提供 -種可製造抑制了料及殘餘應力且品龍之板玻璃的板 玻璃之製造裝置及板玻璃之製造方法。 用以解決課題之手段 為了達成前述目的，本發明的板玻璃之製造裝置發明 係於保持於含有氫氣之還原氣體環境的成形部，將在浮浴 槽上已形成之玻璃帶搬運至氧化氣體環境之徐冷部並徐 冷，藉以製造板玻璃者，其特徵在於：於前述成形部與前 述徐冷部之邊界部，設有再加熱防止機構，該再加熱防止 機構係用以防止起因於成形部内之氫氣的氫火焰所造成之 玻璃帶的再加熱。 為了達成前述目的，本發明的板玻璃之製造方法發明 係使用前述製造裝置，將玻璃帶徐冷以使徐冷部之玻璃帶 溫度到達成形部之玻璃帶溫度以下。 依據本發明，由於可藉由設在成形部與徐冷部之邊界 部的再加熱防止機構，防止成形部内之氫氣滲入至徐冷 部，因此不發生起因於該氫氣之氫火焰，是故，可防止玻 璃帶之再加熱。藉此，自成形部流至徐冷部之破璃帶由於 被徐冷以使其溫度慢慢降低，因此可製造已抑制弯曲及殘 餘應力發生之品質佳的玻璃板。 201006772 依據本發明，前述再加熱防止機構中，前述再加敎防 止機構與前述玻璃帶上面接觸的部分宜由耐熱纖維板構成 者。藉此，成形部之氣體環境與徐冷部之氣體環境由於藉 由接觸構件（财熱纖維板）而完全隔絕，因此可防止成形 4之氫氣滲入至徐冷部。又财熱纖維宜可承受自浮浴槽 =出口拉出之玻璃帶的溫度（在應變點以上軟化點以下的 具體而。電襞顯示器用等之納約玻璃的場合為510 ' 840 c，液晶顯示器用等之無鹼玻璃的場合為6川〜 95〇。〇之材質’亦即可承受贼以上特別是·〇。" φ 上的溫度之材質的纖維為佳。 依據本發明，前述耐熱纖維板係以碳纖維或二氧化矽 矽纖維為佳。又，從低硬度且難以弄傷玻璃帶的觀點來看， 碳纖維較二氧化矽纖維更佳。碳纖維即使假設附著於玻璃 帶的上面，由於會在比較高溫之氧化氣體環境的徐冷部之 下游側燃燒殆盡，因此沒有髒汙等缺點。 而’耐熱纖維並限於碳纖維、二氧化矽纖維，也可為 Λ Ο 銘纖維、碳化矽纖維、及金屬纖維等無機纖維。纖維板係 以毛魅狀之板及織布、或是不織布狀的板為佳。具體而言，t 可使用例如碳纖維之毛氈狀板及碳纖維的織布等。耐熱纖 雉板也可為由相異材質之無機纖維2種以上構成之纖維板。 發明的效果 依據本發明的板玻璃之製造裝置及板玻璃之製造方 法，由於在成形部與徐冷部之邊界部設置再加熱防止機 構，所以可防止起因於氫氣之氫火焰所造成之玻璃帶的再 6 201006772 加熱’藉此可製造抑制了彎曲及殘餘應力發生之品質佳的 板玻璃。本發明係有益於顯示ϋ用板Μ之製造。 圖式簡單說明 圖。第1 ®係顯示實施態樣之麵板製造設備構成之剖面 . f 2 示自錫槽箱通過徐冷部之玻替的溫度變 化之圖表。 • 帛3圖係已設置於第1圖之玻璃板製造設備的再加熱防 止元件之立體圖。 【實施方式；3 _ 用以實施發明之態樣 以下依據添附圖式來就本發明板玻璃之製造裝置及 板玻璃之製造方法的較佳實施態樣進行說明。 第1圖係基於本發明的板玻璃之製造裝置所適用之浮 法的玻璃板製造設備10之刮面圖。而，於以下之說明中， φ 所謂下游側係指以第1圖之玻璃帶12的移動方向為基準且 與其同方向側者（第丨圖之箭頭A方向），並將其相反方向側 稱為上游侧。 顯示於第1圖之玻璃板製造設備10係自上游側朝下游 側設有成形部14及徐冷部16。成形部14係由浮浴槽（熔融 金屬浴槽）18及錫槽箱2〇構成，徐冷部16係由連結部21及 徐冷爐22構成’且於徐冷爐22設有支撐搬運玻璃帶12之徐 冷輥23。 高溫之熔融錫24收容於浮浴槽18，且連續地供給熔融 7 201006772 玻璃至该熔融錫24之水平浴面，藉此朝浮浴槽18之出口 19 形成玻璃帶12。玻璃帶12於浮浴槽18之出口 19，藉由錫浴 槽20之提升輥26A、26B、26C而自熔融錫24被拉出，並在 錫槽箱20内搬運。然後，該玻璃帶12從連結部21被搬出至 徐冷爐22，且在通過該徐冷爐22中慢慢冷卻而製成板玻 璃。而，為錫之熔融溫度以上的氣體環境的浮浴槽18及錫 槽箱20如眾所周知的，由於必須保持於還原（非氧化性）氣體 環境，因此自無圖示之喷嘴經常地供給氮氣(n2)與氫氣出2) 的混合氣體，防止熔融錫24的氧化並保持於正壓。 另一方面，於成形部14與徐冷部16之邊界部設有再加 熱防止機構32，亦即分隔壁15，與該分隔壁15接觸且於該 分隔壁之下部設有與玻璃帶12之上面接觸的耐熱纖維板 30。藉由該耐熱纖維板30來防止因成形部14内之氫氣滲入 至徐冷部16而發生之氫火焰所造成的玻璃帶12之再加熱。 換言之，在實施態樣之玻璃板製造設備1〇，藉由設於 成形部14與徐冷部16之邊界部的再加熱防止機構32，由於 可防止成形部14内之氫氣滲入徐冷部16，所以可防止因氫 氣之滲入而發生之氫火焰所造成的玻璃帶12之再加熱。藉 此’可防止因成形部14内之氫氣滲入徐冷部16而發生之氫 火焰所造成的玻璃帶12之再加熱，且將玻璃帶12徐冷以使 徐冷部16之玻璃帶12的溫度到達成形部14之玻璃帶12的溫 度以下。因而，製造出的板玻璃係已抑制彎曲及殘餘應力 發生之品質佳者。 第2圖係顯示自錫槽箱20通過徐冷部16之電漿顯示器 201006772 面板用玻璃帶的溫度變化之圖表。前述圖形之縱軸表示玻 璃帶12的溫度’橫轴是表示自炼融金屬浴槽18之出口向徐 冷爐22的距離。又，前述圖表中，實線表示將實施態樣之 再加熱防止機構32配置於成形部14與徐冷部16之邊界部時 玻璃帶12的溫度變化，雙點鏈線表示由於未將再加熱防止 機構32配置於前述邊界部’因此氫火焰發生且玻璃帶丨之業 已再加熱時的溫度變化。 在前述圖表之實線所示之態樣中，防止了因成形部14 内之氫氣渗入至徐冷部16而發生之氫火焰所造成之玻璃帶 12的再加熱，且將玻璃帶12徐冷以使徐冷部16之玻璃帶12 的溫度到達成形部14之玻璃帶12的溫度以下。因此，而成 為業已抑制彎曲及殘餘應力發生之品質佳的板玻璃。 相對於此，在以雙點鏈線所示的態樣中，由於在成形 部14與徐冷部16之間發生氫火焰，因此從650。〇慢慢地降低 溫度後的玻璃帶藉由該氫火焰而被加熱，且被再加熱至65〇 〜660°C。因此’成為發生了彎曲及殘餘應力之板玻璃。而， 與對應於該再加熱之尖峰溫度時的實線所示態樣之溫度的 差約為40°C。又’為電漿顯示器用玻璃帶之鈉鈣玻璃時， 如第2圖般，浮浴槽18出口 19之玻璃帶的出口溫度約為 65 0 °C ’但是例如為液晶顯示器面板用玻璃帶之無鹼玻璃的 出口溫度約為750°C。而，與對應於無驗玻璃再加熱之峰值 溫度時的溫度之差也約為4〇。(：。 然而’如第3圖所示，耐熱纖維板30以在玻璃帶12之上 面橫跨玻璃帶12寬度方向的全長而連續地接觸之接觸構件 201006772 為佳。藉此’由於完全阻斷成形部14之氣體環境與徐冷部 16之氣體環境，因此可確實地防止成形部14之氫氣渗入到 徐冷部16。又’耐熱纖維板30之設置位置以最下游侧之提 升輥26C的正上方為佳。 作為實施例，對於自浮浴槽連續地被拉出之鈉鈣玻璃 及無鹼玻璃的玻璃帶，適用再加熱防止機構來進行徐冷。 由於防止了氫火焰所造成之對玻璃帶的再加熱，且徐冷部 之玻璃溫度係成形部的玻璃溫度以下，所以可降低玻璃帶 的彎曲及殘餘應力。 產業上之利用可能性 本發明可利用於依據浮法之建築用板玻璃、汽車用板 玻璃、及顯示器用板玻璃等板玻璃之製造。 而，此處引用了2008年6月6日申請之日本特許申請號 第2008— 149616號之說明書、申請專利範圍、圖式及摘要 的全部内容，並且取入以作為本發明之說明書的揭示。 【圖式簡單說明】 第1圖係顯示實施態樣之玻璃板製造設備的構成之剖 面圖。 第2圖係顯示自錫槽箱通過徐冷部之玻璃帶的溫度變 化之圖表。 第3圖係已設置於第1圖之玻璃板製造設備的再加熱防 止元件之立體圖。 【主要元件符號說明】 ίο 玻璃板製造設備 I2 玻璃帶 201006772 14 成形部 23 徐冷輥 15 分隔壁 24 溶融錫 16 徐冷部 26Α 提升輥 18 浮浴槽 26Β 提升輻； 19 出口 26C 提升輥 20 錫槽箱 30 耐熱纖維板 21 連結部 32 再加熱防止機構 22 徐冷爐 φ 11The tank (dross has been - 卩 徐 徐 徐 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 2010 The molten tin in the floating bath is easily oxidized, so the gas environment of the tin bath is made up of a mixture of rat (N2) gas and hydrogen (a mixture of gas and gas in a reducing gas atmosphere (% concentration 1 12 /, oxygen (〇 2) concentration: l 〇〇ppm or less) is maintained at a positive pressure. Further, the tin tank connected to the float bath is also maintained in a positive pressure reducing gas atmosphere. Moreover, the 〇2 concentration of the oxidizing gas environment of the Xu cold furnace is 5 to 21%. Patent Document 1: International Publication No. WO 02/〇 51767, Γ ^ ^ ^ 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 】 The formed portion of the reducing gas environment is separated from the cold portion of the oxidizing gas environment. However, since the glass ribbon is passed from the forming portion to the quenching furnace, a gap is formed between the upper surface of the glass ribbon and the partition wall. The hydrogen in the tin tank of the shape leaks to the cold portion through the gap, reacts with oxygen near the high temperature glass ribbon to generate a hydrogen flame, and the glass ribbon which has been slowly cooled is re-heated by the hydrogen flame. The problem of heating. Due to the reheating of the glass ribbon, the produced sheet glass is bent and generates residual stress. Therefore, there is a problem that the quality of the sheet glass is lowered. In particular, it is used for a plasma display panel and a liquid crystal display. It is required to reduce the material and _ stress on the panel glass for panel use and the glass for electronic use (solar battery cover glass, magnetic 201006772 disc substrate, etc.) and the 'in the tin tank box' is because the bottom surface of the glass ribbon is lifted. The roller is continuously contacted across the entire width direction thereof, so that a hydrogen flame generated by hydrogen gas leaking from the bottom surface of the glass ribbon to the chilled portion is not generated. The present invention has been completed in view of such circumstances. The object of the invention is to provide a manufacturing apparatus for a sheet glass capable of producing a sheet glass of a product that suppresses a material and residual stress, and a method for producing the sheet glass. Means for Solving the Invention The apparatus for manufacturing a sheet glass according to the present invention is directed to a forming portion held in a reducing gas atmosphere containing hydrogen, and transporting a glass ribbon formed on a floating bath to a cold portion of an oxidizing gas atmosphere And a cold glass, in which the plate glass is manufactured, is characterized in that a reheat prevention mechanism is provided at a boundary portion between the molding portion and the cold portion, and the reheat prevention mechanism is for preventing hydrogen gas from being caused in the forming portion. Reheating of the glass ribbon caused by the hydrogen flame. In order to achieve the above object, the method for producing the sheet glass of the present invention uses the aforementioned manufacturing apparatus to cool the glass ribbon so that the glass ribbon temperature of the cold portion reaches the glass of the forming portion. According to the present invention, since the hydrogen gas in the forming portion can be prevented from infiltrating into the cold portion by the reheat prevention mechanism provided at the boundary portion between the forming portion and the cold portion, the hydrogen flame caused by the hydrogen gas does not occur. Therefore, it can prevent reheating of the glass ribbon. As a result, the glass ribbon flowing from the forming portion to the cold portion is gradually cooled to lower the temperature, so that a glass sheet having excellent quality in which bending and residual stress are suppressed can be produced. According to the present invention, in the reheat prevention mechanism, the portion of the reheating prevention mechanism that is in contact with the upper surface of the glass ribbon is preferably composed of a heat resistant fiber sheet. Thereby, the gas atmosphere of the forming portion and the gas atmosphere of the cold portion are completely isolated by the contact member (the heat fiber board), so that the hydrogen of the forming 4 can be prevented from infiltrating into the cold portion. The heat fiber should be able to withstand the temperature of the glass ribbon from the float bath = the outlet is pulled out (below the softening point above the strain point. The 5% of the glass for the 襞 display is 510 ' 840 c, liquid crystal display When the alkali-free glass is used, it is 6 to 95 〇. The material of 〇 can also withstand the thief, especially the 的. The fiber of the temperature of φ is preferable. According to the present invention, the aforementioned heat-resistant fiberboard It is preferable to use carbon fiber or cerium oxide fiber. Moreover, carbon fiber is more preferable than cerium oxide fiber from the viewpoint of low hardness and difficulty in damaging the glass ribbon. Even if it is assumed to adhere to the glass ribbon, it will be The downstream side of the cold portion of the high-temperature oxidizing gas environment is exhausted, so there is no disadvantage such as dirt. The 'heat-resistant fiber is limited to carbon fiber or cerium oxide fiber, and may be Λ Ο ming fiber, strontium carbide fiber, and Inorganic fiber such as metal fiber. The fiberboard is preferably a sturdy board and a woven fabric or a non-woven fabric. Specifically, t can be used, for example, a carbon fiber felt board and carbon fiber. The heat-resistant fiberboard can also be a fiberboard composed of two or more kinds of inorganic fibers of different materials. Advantageous Effects of Invention According to the apparatus for manufacturing sheet glass of the present invention and the method for producing sheet glass, in the forming section and the Since the reheating prevention mechanism is provided at the boundary portion of the cold portion, it is possible to prevent the glass ribbon from being caused by the hydrogen flame of hydrogen gas to be heated, thereby making it possible to manufacture a plate glass of high quality which suppresses the occurrence of bending and residual stress. The invention is useful for the manufacture of the slabs for the slabs. The figure is a simplified illustration. The 1st series shows the cross-section of the panel manufacturing equipment of the embodiment. The f 2 is shown from the tin tank through the glass of the cold section. Fig. 3 is a perspective view of the reheat prevention element of the glass sheet manufacturing equipment of Fig. 1. [Embodiment; 3 _ for implementing the invention, the following is based on the drawing A preferred embodiment of the apparatus for manufacturing a sheet glass and a method for producing a sheet glass will be described. Fig. 1 is a glass method of a float method applied to a device for manufacturing a sheet glass according to the present invention. In the following description, the term "downstream side" refers to the direction of the movement of the glass ribbon 12 of Fig. 1 and the direction of the same direction (the arrow A direction of the second figure). The glass plate manufacturing apparatus 10 shown in Fig. 1 is provided with a forming portion 14 and a cold portion 16 from the upstream side toward the downstream side. The forming portion 14 is a floating bath ( The molten metal bath 18 and the tin tank 2 are configured, and the cold portion 16 is composed of the connecting portion 21 and the quenching furnace 22, and the Xu cold furnace 22 is provided with a chill roll 23 for supporting the glass ribbon 12. The high temperature molten tin 24 is accommodated. In the float bath 18, the molten glass 7 201006772 is continuously supplied to the horizontal bath surface of the molten tin 24, whereby the glass ribbon 12 is formed toward the outlet 19 of the float bath 18. The glass ribbon 12 is drawn from the molten tin 24 by the lift rolls 26A, 26B, and 26C of the tin bath 20 at the outlet 19 of the float bath 18, and is carried in the tin tank 20. Then, the glass ribbon 12 is carried out from the joint portion 21 to the quenching furnace 22, and is slowly cooled by the quenching furnace 22 to form a sheet glass. Further, as for the floating bath 18 and the tin tank 20 which are gas environments having a melting temperature of tin or more, as is well known, since it is necessary to maintain a reducing (non-oxidizing) gas atmosphere, nitrogen gas is often supplied from a nozzle (not shown) (n2). A mixed gas with hydrogen gas 2) prevents oxidation of the molten tin 24 and maintains it at a positive pressure. On the other hand, a reheat prevention mechanism 32, that is, a partition wall 15 is provided at a boundary portion between the molding portion 14 and the cold portion 16, and is in contact with the partition wall 15 and is provided with a glass ribbon 12 at a lower portion of the partition wall. The heat resistant fiber board 30 that is in contact with it. Reheating of the glass ribbon 12 caused by the hydrogen flame generated by the infiltration of hydrogen gas in the forming portion 14 into the cold portion 16 is prevented by the heat-resistant fiber sheet 30. In other words, in the glass sheet manufacturing apparatus 1 of the embodiment, the reheating prevention mechanism 32 provided at the boundary portion between the molding portion 14 and the cold portion 16 prevents the hydrogen gas in the molding portion 14 from infiltrating into the cold portion 16 Therefore, reheating of the glass ribbon 12 caused by the hydrogen flame generated by the infiltration of hydrogen gas can be prevented. Thereby, the reheating of the glass ribbon 12 caused by the hydrogen flame generated by the hydrogen gas in the forming portion 14 penetrating into the cold portion 16 can be prevented, and the glass ribbon 12 can be cooled to cool the glass ribbon 12 of the cold portion 16. The temperature reaches the temperature of the glass ribbon 12 of the forming portion 14 or less. Therefore, the manufactured sheet glass system has suppressed the quality of the occurrence of bending and residual stress. Fig. 2 is a graph showing the temperature change of the glass ribbon for the panel from the tin tank 20 through the plasma display of the cold portion 16 201006772. The vertical axis of the above graph indicates the temperature of the glass ribbon 12, and the horizontal axis indicates the distance from the outlet of the molten metal bath 18 to the quenching furnace 22. Further, in the above graph, the solid line indicates the temperature change of the glass ribbon 12 when the reheat prevention mechanism 32 of the embodiment is disposed at the boundary between the molding portion 14 and the cold portion 16, and the double-dotted chain indicates that the reheating is not performed. The prevention mechanism 32 is disposed at the boundary portion 'therefore, the temperature change occurs when the hydrogen flame is generated and the glass ribbon is reheated. In the aspect shown by the solid line of the foregoing graph, the reheating of the glass ribbon 12 caused by the hydrogen flame which occurs due to the penetration of hydrogen gas in the forming portion 14 into the cold portion 16 is prevented, and the glass ribbon 12 is cooled. The temperature of the glass ribbon 12 of the cold portion 16 is set to be equal to or lower than the temperature of the glass ribbon 12 of the forming portion 14. Therefore, it is a good quality plate glass which has suppressed the occurrence of bending and residual stress. On the other hand, in the aspect shown by the double-dot chain line, since a hydrogen flame is generated between the forming portion 14 and the cold portion 16, it is from 650. The glass ribbon after the temperature is slowly lowered is heated by the hydrogen flame and reheated to 65 〜 to 660 °C. Therefore, it becomes a plate glass in which bending and residual stress occur. However, the difference in temperature from the solid line corresponding to the peak temperature of the reheating is about 40 °C. Further, when it is a soda lime glass for a glass ribbon for a plasma display, as shown in Fig. 2, the outlet temperature of the glass ribbon at the outlet 19 of the float bath 18 is about 65 0 ° C. 'But for example, there is no glass ribbon for the liquid crystal display panel. The outlet temperature of the alkali glass is about 750 °C. However, the difference from the temperature corresponding to the peak temperature of the reheating without the glass is also about 4 Torr. (: However, as shown in Fig. 3, the heat-resistant fiberboard 30 is preferably a contact member 201006772 which continuously contacts the entire length of the glass ribbon 12 across the width direction of the glass ribbon 12. Thus, due to complete blocking formation The gas atmosphere of the portion 14 and the gas atmosphere of the cold portion 16 can surely prevent the hydrogen gas in the forming portion 14 from penetrating into the cold portion 16. Further, the position of the heat-resistant fiber sheet 30 is directly above the lifting roller 26C on the most downstream side. Preferably, as an embodiment, the reheating prevention mechanism is applied to the glass ribbon of the soda lime glass and the alkali-free glass which are continuously pulled out from the floating bath. Since the hydrogen flame is prevented from being caused by the hydrogen flame, the glass ribbon is prevented. Further, since the glass temperature of the cold portion is equal to or lower than the glass temperature of the molded portion, the bending and residual stress of the glass ribbon can be reduced. INDUSTRIAL APPLICABILITY The present invention can be utilized for a panel glass or a automobile for a floating method. The use of sheet glass, and sheet glass for display panels, etc., and the specification of Japanese Patent Application No. 2008-149616, filed on Jun. 6, 2008, The entire contents of the patent application, the drawings and the abstract are incorporated in the specification of the present disclosure. [FIG. 1] FIG. 1 is a cross-sectional view showing the configuration of a glass sheet manufacturing apparatus of an embodiment. 2 is a graph showing the temperature change of the glass ribbon passing through the tin cold box from the tin tank. Fig. 3 is a perspective view of the reheat prevention element of the glass sheet manufacturing equipment provided in Fig. 1. [Description of main component symbols] Ίο Glass plate manufacturing equipment I2 Glass belt 201006772 14 Forming part 23 Thaw roll 15 Partition wall 24 Dissolved tin 16 Xu cold part 26Α Lifting roll 18 Floating bath 26Β Lifting spoke; 19 Outlet 26C Lifting roll 20 Tin tank 30 Heat-resistant fiber board 21 Connection Part 32 Reheat prevention mechanism 22 Xu cold furnace φ 11